From mboxrd@z Thu Jan 1 00:00:00 1970 From: Minchan Kim Subject: Re: [PATCH] mm: fix build warnings in Date: Fri, 10 Jun 2016 08:51:41 +0900 Message-ID: <20160609235141.GD29779@bbox> References: <5759A1F9.2070302@infradead.org> <20160609152716.1093ada2f52bbcc426e6ddb6@linux-foundation.org> <20160609233143.GC29779@bbox> <20160609163719.5af286badfa9b5314700fece@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Return-path: Received: from LGEAMRELO12.lge.com ([156.147.23.52]:33298 "EHLO lgeamrelo12.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751837AbcFIXuc (ORCPT ); Thu, 9 Jun 2016 19:50:32 -0400 In-Reply-To: <20160609163719.5af286badfa9b5314700fece@linux-foundation.org> Content-Disposition: inline Sender: linux-next-owner@vger.kernel.org List-ID: To: Andrew Morton Cc: Randy Dunlap , Linux MM , "linux-next@vger.kernel.org" , Stephen Rothwell On Thu, Jun 09, 2016 at 04:37:19PM -0700, Andrew Morton wrote: > On Fri, 10 Jun 2016 08:31:43 +0900 Minchan Kim wrote: > > > Hi Andrew, > > > > On Thu, Jun 09, 2016 at 03:27:16PM -0700, Andrew Morton wrote: > > > On Thu, 9 Jun 2016 10:06:01 -0700 Randy Dunlap wrote: > > > > > > > From: Randy Dunlap > > > > > > > > Fix build warnings when struct node is not defined: > > > > > > > > In file included from ../include/linux/balloon_compaction.h:48:0, > > > > from ../mm/balloon_compaction.c:11: > > > > ../include/linux/compaction.h:237:51: warning: 'struct node' declared inside parameter list [enabled by default] > > > > static inline int compaction_register_node(struct node *node) > > > > ../include/linux/compaction.h:237:51: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default] > > > > ../include/linux/compaction.h:242:54: warning: 'struct node' declared inside parameter list [enabled by default] > > > > static inline void compaction_unregister_node(struct node *node) > > > > > > > > ... > > > > > > > > --- linux-next-20160609.orig/include/linux/compaction.h > > > > +++ linux-next-20160609/include/linux/compaction.h > > > > @@ -233,6 +233,7 @@ extern int compaction_register_node(stru > > > > extern void compaction_unregister_node(struct node *node); > > > > > > > > #else > > > > +struct node; > > > > > > > > static inline int compaction_register_node(struct node *node) > > > > { > > > > > > Well compaction.h has no #includes at all and obviously depends on its > > > including file(s) to bring in the definitions which it needs. > > > > > > So if we want to keep that (odd) model then we should fix > > > mm-balloon-use-general-non-lru-movable-page-feature.patch thusly: > > > > How about fixing such odd model in this chance? > > Otherwise, every non-lru page migration driver should include > > both compaction.h and node.h which is weired to me. :( > > > > I think there are two ways. > > > > 1. compaction.h include node.h directly so user of compaction.h don't > > need to take care about node.h > > > > 2. Randy's fix > > > > I looked up who use compaction_[un]register_node and found it's used > > only drivers/base/node.c which already include node.h so no problem. > > > > 1) I believe it's rare those functions to be needed by other files. > > 2) Those functions works if CONFIG_NUMA as well as CONFIG_COMPACTION > > which is rare configuration for many not-server system. > > If we're going to convert compaction.h to be standalone then it will > need to include a whole bunch of things - what's special about node.h? Fair enough. I realize it would be better to relocate non-lru page migration functions to new separate header but I don't have an good idea to name that file. :( Anyway, I will work for it. > > > So, I prefer Randy's fix. > > Doesn't matter much. But note that Randy's patch declared struct node > at line 233. It should be sone at approximatley line 1, to prevent > future duplicated declarations. with removing 218 forward declaration 'struct node;' by me. ;( I'm okay either approach until I fix the problem by introducing new header for non-lru page migration. Thanks!